diff --git a/include/asm-x86/desc_64.h b/include/asm-x86/desc_64.h
index 7d48df72aef2e7349c470b5ba83d4282e13557c3..230ac6e50a0f180502e53b8327d2ce5eb896c882 100644
--- a/include/asm-x86/desc_64.h
+++ b/include/asm-x86/desc_64.h
@@ -215,6 +215,16 @@ static inline void load_LDT(mm_context_t *pc)
 
 extern struct desc_ptr idt_descr;
 
+static inline unsigned long get_desc_base(const void *ptr)
+{
+	const u32 *desc = ptr;
+	unsigned long base;
+	base = ((desc[0] >> 16)  & 0x0000ffff) |
+		((desc[1] << 16) & 0x00ff0000) |
+		(desc[1] & 0xff000000);
+	return base;
+}
+
 #endif /* !__ASSEMBLY__ */
 
 #endif